boxerman
Senior Member
I'm going to try to be helpful for astro beginners, but best start with a photo:
Light painted rocks in Joshua Tree National Park; You ca see a lot of airplane blinking lights. Ugh.
Equipment and setup:
E-M1 II with Rokinon 12mm f/2, using live comp. exposure setting (combines multiple shots in-camera, on the basis of "brightest pixel"). Something like 180 x 30 sec shots at ISO 200, f/2. Tripod. Light painted with a 6V "camping lantern" flashlight. Tripod. Petzl (headband flashlight, with a very low setting not to bother your eyes for the darkness). I used a cheapo manual exposure release cable, but I'm sure linking to your phone would be fine. Probably better, except for how easy and effective the cable is.
After my first astro session, described below, I wanted to add three genres of astro shooting to my repertoire. I wanted to try live composite, get a Milky Way shot, and also get maybe 8-16 shots to stack for a single frame, but reduced noise. The weather did not cooperate. Too many clouds for Milky Way (and Joshua Tree is not into true dark skies, still light from the LA area). And besides, it was really not a great time of year for the Milky way, which doesn't get vertical, and does not get that far above the horizon at this time of year (April).
I had learned that for shooting stars, a good "reference" exposure is 30 secs, f/2.0, ISO 200, just what I did here and in the Kalahari, previously. I found it JUST gets to saturating the brightest stars, so saves all the color that's there, much more than you can see with your eye. My first astro shoot was in one of the best astro shooting locations in the world, but the identical exposure worked excellently. People new to astro worry too much, in my view, about exposure; it's pretty stable, no need to fret. For Milky Way, however, you would do well to add at least 3 stops of exposure to my reference.
I had learned in my first session that getting pin-point stars is a trick. Unless you use a tracker to cancel the rotation of the earth, you begin getting streaks, according to the rule of 500, at 12.5 secs with my 20 mm, at about 20 secs for 12 mm m4/3. So, in fact, my goal for pin-point is more like "the rule of 150 / <m43-FL>. Would be the rule of 300 for full-frame FL. This is dependent on your personal sensitivity and output method. We print up to 40 inches, and I'm pretty sensitive, hence the "rule of 150". Obviously, this is not an issue at all if you're doing star streaks.
Wider lens gets you better (longer) shutter durations before streaking, so I upgraded my "astro lens" from my firsts session from Panny 20mm to Rokinon 12 mm. Rokinon is cheap and quite good optical quality. The manual focus is actually a help, and you can focus once during daylight, and then mark the lens so you can return to infinity whenever you want. I put a small bit of tape, marked with a pen, so easily retrieve infinite focus. (The Rokinon's in-built scale is inaccurate, so calibration is needed.)
Live composite worked like a charm. (But learn how to use it before you go out. It's a little tricky.) Completely easy (once you know what you're doing and set up the base exposure). I did one and only one sequence. The unfortunately bright sky--full moon and (thin) clouds--was a bit of a problem. On the one hand, the lighting of the rocks was accidentally nearly perfect--I had only to fill in with my flashlight a TINY bit in the darkest parts of the rocks--only during a small part of the first or second 30 sec exposure. (The camera only updates the screen after each full--30 secs--exposure. So, you have to guess on amount of painting light. Guess low, do more in later exposures, if necessary.) But, the sky, although it appears dark to the eye, was definitely not dark to the camera. Here's the SOOC image:
SOOC version of the above photo
The blue background has its own charm, but I decided I liked a darker background better. Luckily, post processing was very easy. I darkened the exposure just a hair, turned down the blue channel as far as possible (which had almost no effect on the orange rocks), and then boosted orange and yellow in the Olympus color wheel, to get the rocks back to about where they were in the original. Used Olympus Workspace for the PP.
Final point: I was worried about battery life. For my first astro shoot, I worked to keep both screen and viewfinder off (was not easy). But, with this long exposure and the LCD constantly on (for live composite), I used only a small fraction of the E-M1 II battery. I'll have no worries (but still a backup battery) in the future.
Prepping:
I did a fair amount of scouting out during the day to find a good rock location. In the end, though, I took second or third best. I just did not feel secure hiking around at night in the dark (just about midnight) and very rocky terrain. So, I settled for something only a few minutes' hike off the road. As it was, I'd hoped to position the Pole Star right in the gap in the rocks. But, that, in fact, required an angle that shrank the rock gap almost to nothing. I decided just to ignore Pole positioning, and go with the nicest (biggest) gap. Maybe I'll be braver hiking at night next time. In any case, scouting is highly recommended.
My First Shoot (2014):
My first astro shooting was in the Kalahari Desert. I had just done some reading about exposure, took exactly one "test" shot at a safari camp before we got to the Kalahari, and then set up my camera (E-M5) and took 150 x 30 sec shots. (It was a trick to d that as the E-M5 did not have good multiple-shoot options. I had to use shutter-delay "hack" to get it to work.) Combined all the pictures when I got home in multiple ways, including to make full streaks, time lapse, and movies that showed the streak in formation, starting with still number one (adding new shots, one at a time until it included all the series), followed by streak gradually disappearing (segment starting from full set, eliminating one from the beginning at a time, to the final shot).
Lessons learned in the Kalahari:
--
The BoxerMan
Light painted rocks in Joshua Tree National Park; You ca see a lot of airplane blinking lights. Ugh.
Equipment and setup:
E-M1 II with Rokinon 12mm f/2, using live comp. exposure setting (combines multiple shots in-camera, on the basis of "brightest pixel"). Something like 180 x 30 sec shots at ISO 200, f/2. Tripod. Light painted with a 6V "camping lantern" flashlight. Tripod. Petzl (headband flashlight, with a very low setting not to bother your eyes for the darkness). I used a cheapo manual exposure release cable, but I'm sure linking to your phone would be fine. Probably better, except for how easy and effective the cable is.
After my first astro session, described below, I wanted to add three genres of astro shooting to my repertoire. I wanted to try live composite, get a Milky Way shot, and also get maybe 8-16 shots to stack for a single frame, but reduced noise. The weather did not cooperate. Too many clouds for Milky Way (and Joshua Tree is not into true dark skies, still light from the LA area). And besides, it was really not a great time of year for the Milky way, which doesn't get vertical, and does not get that far above the horizon at this time of year (April).
I had learned that for shooting stars, a good "reference" exposure is 30 secs, f/2.0, ISO 200, just what I did here and in the Kalahari, previously. I found it JUST gets to saturating the brightest stars, so saves all the color that's there, much more than you can see with your eye. My first astro shoot was in one of the best astro shooting locations in the world, but the identical exposure worked excellently. People new to astro worry too much, in my view, about exposure; it's pretty stable, no need to fret. For Milky Way, however, you would do well to add at least 3 stops of exposure to my reference.
I had learned in my first session that getting pin-point stars is a trick. Unless you use a tracker to cancel the rotation of the earth, you begin getting streaks, according to the rule of 500, at 12.5 secs with my 20 mm, at about 20 secs for 12 mm m4/3. So, in fact, my goal for pin-point is more like "the rule of 150 / <m43-FL>. Would be the rule of 300 for full-frame FL. This is dependent on your personal sensitivity and output method. We print up to 40 inches, and I'm pretty sensitive, hence the "rule of 150". Obviously, this is not an issue at all if you're doing star streaks.
Wider lens gets you better (longer) shutter durations before streaking, so I upgraded my "astro lens" from my firsts session from Panny 20mm to Rokinon 12 mm. Rokinon is cheap and quite good optical quality. The manual focus is actually a help, and you can focus once during daylight, and then mark the lens so you can return to infinity whenever you want. I put a small bit of tape, marked with a pen, so easily retrieve infinite focus. (The Rokinon's in-built scale is inaccurate, so calibration is needed.)
Live composite worked like a charm. (But learn how to use it before you go out. It's a little tricky.) Completely easy (once you know what you're doing and set up the base exposure). I did one and only one sequence. The unfortunately bright sky--full moon and (thin) clouds--was a bit of a problem. On the one hand, the lighting of the rocks was accidentally nearly perfect--I had only to fill in with my flashlight a TINY bit in the darkest parts of the rocks--only during a small part of the first or second 30 sec exposure. (The camera only updates the screen after each full--30 secs--exposure. So, you have to guess on amount of painting light. Guess low, do more in later exposures, if necessary.) But, the sky, although it appears dark to the eye, was definitely not dark to the camera. Here's the SOOC image:
SOOC version of the above photo
The blue background has its own charm, but I decided I liked a darker background better. Luckily, post processing was very easy. I darkened the exposure just a hair, turned down the blue channel as far as possible (which had almost no effect on the orange rocks), and then boosted orange and yellow in the Olympus color wheel, to get the rocks back to about where they were in the original. Used Olympus Workspace for the PP.
Final point: I was worried about battery life. For my first astro shoot, I worked to keep both screen and viewfinder off (was not easy). But, with this long exposure and the LCD constantly on (for live composite), I used only a small fraction of the E-M1 II battery. I'll have no worries (but still a backup battery) in the future.
Prepping:
I did a fair amount of scouting out during the day to find a good rock location. In the end, though, I took second or third best. I just did not feel secure hiking around at night in the dark (just about midnight) and very rocky terrain. So, I settled for something only a few minutes' hike off the road. As it was, I'd hoped to position the Pole Star right in the gap in the rocks. But, that, in fact, required an angle that shrank the rock gap almost to nothing. I decided just to ignore Pole positioning, and go with the nicest (biggest) gap. Maybe I'll be braver hiking at night next time. In any case, scouting is highly recommended.
My First Shoot (2014):
My first astro shooting was in the Kalahari Desert. I had just done some reading about exposure, took exactly one "test" shot at a safari camp before we got to the Kalahari, and then set up my camera (E-M5) and took 150 x 30 sec shots. (It was a trick to d that as the E-M5 did not have good multiple-shoot options. I had to use shutter-delay "hack" to get it to work.) Combined all the pictures when I got home in multiple ways, including to make full streaks, time lapse, and movies that showed the streak in formation, starting with still number one (adding new shots, one at a time until it included all the series), followed by streak gradually disappearing (segment starting from full set, eliminating one from the beginning at a time, to the final shot).
Lessons learned in the Kalahari:
- I trust my "standard" astro exposure quite a lot, now. So, I'd always start there (for stars alone, not Milky Way). I found that PP could make a HUGE difference, as I did manage to PP to make the Milky Way passable, even thought the exposure I used was at least three stops low.
- M4/3 is at the edge of performance for noise for astro shooting. Hence, I'm going to get to mutiple combined shots in the future, to reduce noise.
- I intended to create movies, so set my E-M5 to 16x9, and mid-level resolution. Big mistake. You can always crop, and while I was worried about filling my card with the E-M5, big cards available now make this a non-issue. I'm back to my standard: RAW + jpg, highest quality. Astro shoots to me are "scarce resources." Make the best use (flexible shooting) of each one.
--
The BoxerMan
